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The use of computerized simulation of pouring and solidification for the optimization of production and properties of castings has considerably increased in recent years. Today, mature software packages are commercially available to the foundry industry. Modern simulation programs now also enable the calculation of mold filling, internal stresses, microstructure, and casting properties.In order to improve further the results of simulation calculations, particularly at long solidification and cooling times, work has been carried out to establish more precise physical data for the mold materials and the coefficients of heat transfer between the casting and the sand mold.Today mold materials are constantly being improved, new materials (sands) are being tried, and new additives are being developed. So it would be helpful to be able to determine the thermophysical properties of new mold materials. The measuring methods used for determination of the thermophysical parameters must therefore also be available for the investigation of work-specific and/or future mold materials. The measuring methods should be able to establish reliable data at an acceptable cost.A number of projects have previously dealt with the question of heat transport in molds. However, the results are inadequate for the requirements of modern simulation techniques.The Institut für Gieûereitechnik, Düsseldorf, has carried out a research project to investigate and establish the relevant thermophysical properties of resin-bonded and bentonitebonded operational mold materials and laboratory mixtures. The following information is mainly concerned with cold resin-bonded mold materials (nobake sands); large castings that have long solidification and cooling times are predominantly produced in nobake sand molds. A comprehensive review will be published soon. [1] Mold materials are mixtures consisting of basic materials (sands), binders and, if necessary, additives and water. The specific thermal capacities of typical basic materials such as quartz, zirconium, or chromite sands were taken from a relevant collection of data. [2] The exothermic and endothermic reactions occurring during heating were determined up to 1100 C by means of a Netsch DSC 404 differential scanning calorimeter.In an inert gas atmosphere (pure argon) the nobake sand samples with 0.9 % resin and 0.5 % paratoluene sulfonicacid (PTS) hardener (both mass fractions) exhibit exothermal reactions in the range 16 000±37 500 J/kg in the temperature range from about 325 to over 525 C (Fig. 1). There is no detectable difference between the thermal effects when using furan or phenolic resin binders.With increasing temperature in air an exothermic reaction begins at about 200 C and ends at around 550 C; a heat of reaction of 229 700 J/kg was measured.The values for the specific thermal capacity of individual basic sands are only dependent on the temperature, whilst the enthalpies of the binder (resin, bentonite, or waterglass) are dependent on both the temperature and the temperature progression (i...